A control and rectification circuit of a full-bridge active bridge

Abstract

This invention belongs to the field of electronic circuit technology, specifically relating to a control and rectification circuit for a full-bridge active bridge. Addressing the problems of high losses and severe heat generation caused by the on-state voltage drop in traditional diode rectifier bridges under low input voltage and high power output scenarios, this invention proposes replacing four rectifier diodes with MOSFETs or GaN devices. The circuit includes a full-bridge rectification module, a low-frequency drive module, a high-frequency oscillation module, and a resonant drive module. Utilizing the zero-crossing characteristic of the AC input voltage, the low-side switching transistor is directly driven by an emitter follower; simultaneously, a 385kHz high-frequency signal is generated by a high-frequency signal generator, which is absorbed and coupled through an LC resonant network to induce a drive voltage at the gate of the floating high-side switching transistor. This invention achieves synchronous rectification control of the full-bridge active devices without the need for an isolation transformer or dedicated driver chip, significantly reducing conduction losses, improving system efficiency, and effectively solving the heat dissipation problem in high-power applications.

Description

Technical Field

[0001] This invention belongs to the field of electronic circuit technology, specifically relating to a control and rectification circuit for a full-bridge active bridge. Background Technology

[0002] In existing switching power supplies, the common rectifier circuit typically uses four diodes to form a bridge rectifier, converting the input AC voltage to DC voltage. However, in applications with low input voltage and high power output, the current flowing through the diodes is usually very large, for example, exceeding 3A. Since the forward voltage drop (VF) of a diode is typically between 0.7V and 1V, this results in significant power losses from the four rectifier diodes. Taking a current of 3A and a forward voltage drop of VF = 0.8V as an example, the loss of a single diode is Ploss = VF × I = 0.8V × 3A = 2.4W, and the total loss of the four diodes reaches as high as 9.6W. This not only significantly reduces the system's conversion efficiency but also poses a serious heat dissipation problem in engineering, increasing the cost and size of heat sinks and fans.

[0003] To address the issue of high conduction losses in diodes, the industry has proposed using MOSFETs or GaN devices with low on-resistance to replace diodes for synchronous rectification. Taking a 3A current as an example, if a MOSFET with an on-resistance of 60mΩ is used, its conduction loss is only Ploss = I² × Rds(on) = 3² × 0.06 = 0.54W, approximately one-fifth of the diode loss. However, MOSFETs or GaN devices are voltage-controlled devices and cannot automatically conduct unidirectionally like diodes; they require a suitable gate drive signal to function properly. In a full-bridge rectifier structure, the two high-side switching devices are in a floating state, and providing them with drive signals has always been a technical challenge. Therefore, this invention provides a full-bridge active bridge control and rectification circuit. Summary of the Invention

[0004] The purpose of this invention is to provide a control and rectification circuit for a full-bridge active bridge, which uses the zero-crossing characteristics of the AC input voltage to generate a low-frequency drive signal and uses the coupling resonance principle of the high-frequency signal to generate a drive signal for the high-end floating ground switching device, thereby replacing the traditional diode with a MOSFET or GaN device, significantly reducing conduction losses and improving system efficiency.

[0005] The specific technical solution adopted by this invention is as follows: A control and rectification circuit for a full-bridge active bridge includes: The full-bridge rectifier module consists of four power switching devices, including a high-side half-bridge and a low-side half-bridge. The high-side half-bridge is composed of a first power switching device M1 and a second power switching device M2, and is floating relative to the DC bus. The low-side half-bridge is composed of a third power switching device M3 and a fourth power switching device M4, and is connected to the system reference ground. The AC input terminals AC_L and AC_N are respectively connected to the diagonal nodes of the full-bridge rectifier module. The low-frequency drive module is used to detect the polarity of the AC input voltage. When the AC input voltage is in the corresponding polarity, it uses the AC input voltage to drive the corresponding low-side power switching device to turn on through the emitter follower, and at the same time turns off the low-side power switching device on the other side through the clamping diode. A high-frequency oscillation module is used to generate a fixed-frequency high-frequency oscillation signal. The signal distribution and switching module, connected to the low-frequency drive module and the high-frequency oscillation module, is used to selectively distribute the high-frequency oscillation signal to one side of the high-end half-bridge according to the polarity of the AC input voltage. The resonant drive module is connected between the signal distribution and switching module and the high-side half-bridge. It is used to receive the distributed high-frequency signal, generate a high-frequency induced voltage through LC resonance absorption, and rectify it to generate a DC drive voltage to drive the corresponding high-side power switching device to turn on.

[0006] Preferably, the low-frequency drive module includes: The first low-frequency drive unit is connected between the AC input terminal AC_L and the gate of the fourth power switching device M4. It is configured to apply the auxiliary power supply voltage Va to the gate of M4 through the emitter follower function of the transistor Q5 when AC_L is positive. The second low-frequency drive unit is connected between the AC input terminal AC_N and the gate of the third power switching device M3. It is configured to apply the auxiliary power supply voltage Va to the gate of M3 through the emitter follower function of the transistor Q6 when AC_N is positive. The first turn-off clamping unit includes a diode D17 connected between AC_N and the gate of M3, configured to turn on and pull down the gate voltage of M3 when M4 is turned on, causing the AC_N potential to approach the ground potential. The second turn-off clamping unit includes a diode D16 connected between AC_L and the gate of M4, configured to turn on and pull down the gate voltage of M4 when M3 is turned on, causing the AC_L potential to approach the ground potential.

[0007] Preferably, the signal distribution and switching module includes: The first switching transistor Q8 has its control terminal connected to the gate of the fourth power switching device M4 and is controlled by the gate voltage of M4. The second switch Q9 has its control terminal connected to the gate of the third power switch M3 and is controlled by the gate voltage of M3. When the gate of M4 is high, Q8 is turned off, allowing high-frequency signals to be transmitted to the first resonant branch through the first amplification branch Q2 and Q3; at the same time, when the gate of M3 is low, Q9 is turned on, short-circuiting the second amplification branch Q4 and Q7, and preventing high-frequency signals from being transmitted to the second resonant branch. When the gate of M3 is high, Q9 is turned off, allowing high-frequency signals to be transmitted to the second resonant branch through the second amplification branch; at the same time, when the gate of M4 is low, Q8 is turned on, short-circuiting the first amplification branch and preventing high-frequency signals from being transmitted to the first resonant branch.

[0008] Preferably, the resonant drive module includes: The first resonant unit, connected to the first power switching device M1 of the high-end half-bridge, consists of a resonant inductor L2 and a resonant capacitor C9. The second resonant unit, connected to the second power switching device M2 of the high-end half-bridge, consists of a resonant inductor L3 and a resonant capacitor C12. The first rectifier unit, connected to the output terminal of the first resonant unit, consists of high-frequency diodes D1 and D7 and filter capacitors C10 and C11, and is configured to rectify the resonant voltage into a DC voltage to drive M1. The second rectifier unit, connected to the output of the second resonant unit, consists of high-frequency diodes D5 and D4 and filter capacitors C13 and C14, and is configured to rectify the resonant voltage into a DC voltage to drive M2.

[0009] Preferably, it further includes a gate discharge unit, including transistors Q10 and Q11 connected between the gate and source of the high-side power switching device, configured to short-circuit the gate of the high-side power switching device to the source when the corresponding resonant signal is cut off, thereby ensuring its turn-off.

[0010] Preferably, the power switching device is a MOSFET, SiCMOSFET, or GaN device.

[0011] Preferably, the frequency of the high-frequency oscillation signal generated by the high-frequency oscillation module is 385kHz.

[0012] The technical effects achieved by this invention are as follows: This invention offers high efficiency: by replacing diodes with low-resistance MOSFETs / GaN, conduction losses are significantly reduced, making it particularly suitable for low-voltage, high-current applications.

[0013] This invention eliminates the need for an isolation transformer: by utilizing the resonant coupling principle of high-frequency signals, it cleverly solves the problem of high-end floating ground drive, eliminating the need for traditional bootstrap circuits or auxiliary isolation transformers, thus saving cost and size.

[0014] The control logic of this invention is simple: it uses the AC input voltage itself as the control signal source, eliminating the need for complex dedicated control chips and ensuring high circuit reliability. This invention uses the generated drive signal to drive MOSFETs or GaN devices to replace ordinary diode rectification, significantly improving efficiency at low voltage input and high power output, reducing heat generation, lowering energy consumption, and eliminating the need for raw materials such as copper or aluminum heat sinks to handle heat. Attached Figure Description

[0015] Figure 1 This is a circuit diagram of a control and rectification circuit for a full-bridge active bridge according to the present invention.

[0016] Figure 2 This is a schematic diagram of the working waveforms of the relevant nodes in this invention. Detailed Implementation

[0017] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.

[0018] Example 1: Circuit Structure like Figure 1 As shown, a control and rectification circuit for a full-bridge active bridge includes: The full-bridge rectifier module consists of four power switching devices, including a high-side half-bridge and a low-side half-bridge. The high-side half-bridge is composed of a first power switching device M1 and a second power switching device M2, and is floating relative to the DC bus. The low-side half-bridge is composed of a third power switching device M3 and a fourth power switching device M4, and is connected to the system reference ground. The AC input terminals AC_L and AC_N are respectively connected to the diagonal nodes of the full-bridge rectifier module. The low-frequency drive module is used to detect the polarity of the AC input voltage. When the AC input voltage is in the corresponding polarity, it uses the AC input voltage to drive the corresponding low-side power switching device to turn on through the emitter follower, and at the same time turns off the low-side power switching device on the other side through the clamping diode. A high-frequency oscillation module is used to generate a fixed-frequency high-frequency oscillation signal. The signal distribution and switching module, connected to the low-frequency drive module and the high-frequency oscillation module, is used to selectively distribute the high-frequency oscillation signal to one side of the high-end half-bridge according to the polarity of the AC input voltage. The resonant drive module is connected between the signal distribution and switching module and the high-side half-bridge. It is used to receive the distributed high-frequency signal, generate a high-frequency induced voltage through LC resonance absorption, and rectify it to generate a DC drive voltage to drive the corresponding high-side power switching device to turn on.

[0019] Preferably, the low-frequency drive module includes: The first low-frequency drive unit is connected between the AC input terminal AC_L and the gate of the fourth power switching device M4. It is configured to apply the auxiliary power supply voltage Va to the gate of M4 through the emitter follower function of the transistor Q5 when AC_L is positive. The second low-frequency drive unit is connected between the AC input terminal AC_N and the gate of the third power switching device M3. It is configured to apply the auxiliary power supply voltage Va to the gate of M3 through the emitter follower function of the transistor Q6 when AC_N is positive. The first turn-off clamping unit includes a diode D17 connected between AC_N and the gate of M3, configured to turn on and pull down the gate voltage of M3 when M4 is turned on, causing the AC_N potential to approach the ground potential. The second turn-off clamping unit includes a diode D16 connected between AC_L and the gate of M4, configured to turn on and pull down the gate voltage of M4 when M3 is turned on, causing the AC_L potential to approach the ground potential.

[0020] Preferably, the signal distribution and switching module includes: The first switching transistor Q8 has its control terminal connected to the gate of the fourth power switching device M4 and is controlled by the gate voltage of M4. The second switch Q9 has its control terminal connected to the gate of the third power switch M3 and is controlled by the gate voltage of M3. When the gate of M4 is high, Q8 is turned off, allowing high-frequency signals to be transmitted to the first resonant branch through the first amplification branch Q2 and Q3; at the same time, when the gate of M3 is low, Q9 is turned on, short-circuiting the second amplification branch Q4 and Q7, and preventing high-frequency signals from being transmitted to the second resonant branch. When the gate of M3 is high, Q9 is turned off, allowing high-frequency signals to be transmitted to the second resonant branch through the second amplification branch; at the same time, when the gate of M4 is low, Q8 is turned on, short-circuiting the first amplification branch and preventing high-frequency signals from being transmitted to the first resonant branch.

[0021] Preferably, the resonant drive module includes: The first resonant unit, connected to the first power switching device M1 of the high-end half-bridge, consists of a resonant inductor L2 and a resonant capacitor C9. The second resonant unit, connected to the second power switching device M2 of the high-end half-bridge, consists of a resonant inductor L3 and a resonant capacitor C12. The first rectifier unit, connected to the output terminal of the first resonant unit, consists of high-frequency diodes D1 and D7 and filter capacitors C10 and C11, and is configured to rectify the resonant voltage into a DC voltage to drive M1. The second rectifier unit, connected to the output of the second resonant unit, consists of high-frequency diodes D5 and D4 and filter capacitors C13 and C14, and is configured to rectify the resonant voltage into a DC voltage to drive M2.

[0022] Preferably, it further includes a gate discharge unit, including transistors Q10 and Q11 connected between the gate and source of the high-side power switching device, configured to short-circuit the gate of the high-side power switching device to the source when the corresponding resonant signal is cut off, thereby ensuring its turn-off.

[0023] Preferably, the power switching device is a MOSFET, SiCMOSFET, or GaN device.

[0024] Preferably, the frequency of the high-frequency oscillation signal generated by the high-frequency oscillation module is 385kHz.

[0025] Example 2: When the AC input is positive (AC_L) and negative (AC_N), MOSFETs or GaN devices M1 and M4 are required to be turned on to replace D2 and D13 to complete the rectification of the positive half-cycle. During this process, M2 and M3 must be turned off, otherwise the input voltage will be short-circuited.

[0026] When AC_L is positive, the fast diode D16 is blocked. The input voltage is clamped and regulated to around 18.6V at the base of transistor Q5 through diode D10 and current-limiting resistor R12 via Zener diode D11. Through the emitter follower effect of transistor Q5, the 20V auxiliary power supply Va is applied to the gate of M4 through Q5, thereby turning on M4 and allowing the rectified current of the positive half-cycle to flow normally.

[0027] Meanwhile, the high-frequency signal generated by Q1 passes through C8 and R5. Since the gate terminal LL of M4 is at a high voltage at this time, Q8 is in the off state and has no effect on the high-frequency signal. After being amplified by Q2 and Q3, the high-frequency signal enters the resonant circuit composed of C9 / L2 through R8. A high-frequency voltage is generated at the two ends of L2 due to resonance absorption. This high-frequency voltage generates a 10V-20V driving voltage through components such as C10, D1, D7, C11, R10, and D3 and is applied to the gate of M1, thereby turning on M1 and allowing the rectified current of the positive half-cycle to flow normally.

[0028] At the same time, AC_N is negative. Since M4 is in the on state at this time, the voltage of AC_N to the circuit ground is close to 0V. Therefore, the cathode of D17 is at a low level, and diode D17 is naturally turned on, pulling the gate (LN) terminal of M3 down to a voltage close to 0V, thereby ensuring that M3 is in the off state.

[0029] Since the gate (LN) terminal of M3 is close to 0V, Q9 connected to this terminal is turned on, shorting the bases of Q4 and Q7 to ground. The high-frequency signal generated by Q1 cannot pass through the R22 / C12 / L3 network. The gate of the MOSFET or GaN device M2 is shorted to the source by Q11, thus ensuring that M2 is in the off state.

[0030] Therefore, when AC_L is positive and AC_N is negative, the circuit can guarantee the correct state of M1 and M4 being turned on and M2 and M3 being turned off.

[0031] Example 3: When the AC input is negative (AC_L) and positive (AC_N), MOSFETs or GaN devices M2 and M3 are required to be turned on to replace D6 and D9 to complete the rectification of the positive half-cycle. During this process, M1 and M4 must be turned off, otherwise the input voltage will be short-circuited.

[0032] When AC_N is positive, the fast diode D17 is blocked. The input voltage is clamped and regulated to around 18.6V at the base of transistor Q6 through diode D15 and current-limiting resistor R15 via Zener diode D14. Through the emitter follower effect of transistor Q6, the 20V auxiliary power supply Va is applied to the gate of M3 through Q6, thereby turning on M3 and allowing the rectified current of the negative half-cycle to flow normally.

[0033] Meanwhile, the high-frequency signal generated by Q1 passes through C15 and R19. Since the gate LN of M3 is at a high voltage at this time, Q9 is in the off state and has no effect on the high-frequency signal. After being amplified by Q4 and Q7, the high-frequency signal enters the resonant circuit composed of C12 / L3 through R22. A high-frequency voltage is generated at the L3 terminals due to resonance absorption. This high-frequency voltage generates a 10V-20V driving voltage through components such as C13, D5, D4, C14, R23, and D8, which is applied to the gate of M2, thereby turning on M2 and allowing the rectified current of the negative half-cycle to flow normally.

[0034] At the same time, AC_L is negative. Since M3 is on at this time, the voltage of AC_L to the circuit ground is close to 0V. Therefore, the cathode of D16 is at a low level, and diode D16 is naturally turned on, pulling the gate (LL) terminal of M4 down to a voltage close to 0V, thereby ensuring that M4 is in the off state.

[0035] Since the gate (LL) terminal of M4 is close to 0V, Q8 connected to this terminal is turned on, shorting the bases of Q2 and Q3 to ground. The high-frequency signal generated by Q1 cannot pass through the R8 / C9 / L2 network. The gate of the MOSFET or GaN device M1 is shorted to the source by Q10, thus ensuring that M1 is in the off state.

[0036] Therefore, when AC_L is negative and AC_N is positive, the circuit can guarantee the correct state of M2 and M3 being turned on and M1 and M4 being turned off.

[0037] This invention utilizes the characteristic that each node of the current circuit is equivalent to a direct pass at high frequencies, and generates the drive signal required by the active devices MOSFET or GaN of the high-end half-bridge through the effective transmission of high-frequency energy.

[0038] Figure 2 The diagram shows the current and voltage waveforms of the various key components in the circuit mentioned in this invention during normal operation.

[0039] The bottom layer of the diagram shows the waveform between the input voltages (V1) AC_L and AC_N; the second layer below shows the current waveform when the two MOSFET / GaN devices M3 and M4 of the low-end half-bridge alternately carry current; the third layer below shows the current waveform when the two MOSFET / GaN devices M1 and M2 of the high-end half-bridge alternately carry current.

[0040] The top layer of the waveform in the figure shows the drive control voltage between the gate and source of the two MOSFET / GaN devices M1 and M2 in the high-side half-bridge mentioned in the circuit; the second layer above the figure shows the drive control voltage between the gates of the two MOSFET / GaN devices M3 and M4 in the low-side half-bridge during normal operation.

[0041] This invention utilizes the principle of resonant absorption to provide an effective driving signal to nodes where it is inconvenient to provide DC voltage, taking advantage of the characteristic that only high-frequency voltages of a specific frequency can transmit energy.

[0042] This invention uses a small-capacity high-voltage capacitor to achieve resonance in the LC circuit and effectively isolate the power frequency and DC potential at each node of the rectifier circuit.

[0043] This invention generates a suitable drive signal for MOSFET or GaN devices by clamping the AC input voltage.

[0044] This invention utilizes the voltage drop near the zero-crossing point of the AC input voltage to automatically turn off MOSFET or GaN devices via a fast diode.

[0045] This invention uses the generated drive signal to drive MOSFET or GaN devices to replace ordinary diode rectification, which can significantly improve efficiency at low voltage input and high power output, reduce heat generation, reduce energy consumption, and reduce the use of raw materials such as copper or aluminum heat sinks to handle heat generation.

[0046] This invention proposes replacing four rectifier diodes with MOSFETs or GaN devices. The circuit includes a full-bridge rectifier module, a low-frequency drive module, a high-frequency oscillation module, and a resonant drive module. Utilizing the zero-crossing characteristic of the AC input voltage, the low-side switching transistor is directly driven by an emitter follower; simultaneously, a 385kHz high-frequency signal is generated by a high-frequency signal generator, which is absorbed and coupled through an LC resonant network to induce a drive voltage at the gate of the floating high-side switching transistor. This invention achieves synchronous rectification control of full-bridge active devices without the need for isolation transformers or dedicated driver chips, significantly reducing conduction losses, improving system efficiency, and effectively solving the heat dissipation problem in high-power applications.

[0047] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention are implemented according to conventional methods in the art unless otherwise specified or limited.

Claims

1. A control and rectification circuit for a full-bridge active bridge, characterized in that: include: The full-bridge rectifier module consists of four power switching devices, including a high-side half-bridge and a low-side half-bridge. The high-side half-bridge is composed of a first power switching device M1 and a second power switching device M2, and is floating relative to the DC bus. The low-side half-bridge is composed of a third power switching device M3 and a fourth power switching device M4, and is connected to the system reference ground. The AC input terminals AC_L and AC_N are respectively connected to the diagonal nodes of the full-bridge rectifier module. The low-frequency drive module is used to detect the polarity of the AC input voltage. When the AC input voltage is in the corresponding polarity, it uses the AC input voltage to drive the corresponding low-side power switching device to turn on through the emitter follower, and at the same time turns off the low-side power switching device on the other side through the clamping diode. A high-frequency oscillation module is used to generate a fixed-frequency high-frequency oscillation signal. The signal distribution and switching module, connected to the low-frequency drive module and the high-frequency oscillation module, is used to selectively distribute the high-frequency oscillation signal to one side of the high-end half-bridge according to the polarity of the AC input voltage. The resonant drive module is connected between the signal distribution and switching module and the high-side half-bridge. It is used to receive the distributed high-frequency signal, generate a high-frequency induced voltage through LC resonance absorption, and rectify it to generate a DC drive voltage to drive the corresponding high-side power switching device to turn on.

2. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: The low-frequency drive module includes: The first low-frequency drive unit is connected between the AC input terminal AC_L and the gate of the fourth power switching device M4. It is configured to apply the auxiliary power supply voltage Va to the gate of M4 through the emitter follower function of the transistor Q5 when AC_L is positive. The second low-frequency drive unit is connected between the AC input terminal AC_N and the gate of the third power switching device M3. It is configured to apply the auxiliary power supply voltage Va to the gate of M3 through the emitter follower function of the transistor Q6 when AC_N is positive. The first turn-off clamping unit includes a diode D17 connected between AC_N and the gate of M3, configured to turn on and pull down the gate voltage of M3 when M4 is turned on, causing the AC_N potential to approach the ground potential. The second turn-off clamping unit includes a diode D16 connected between AC_L and the gate of M4, configured to turn on and pull down the gate voltage of M4 when M3 is turned on, causing the AC_L potential to approach the ground potential.

3. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: The signal distribution and switching module includes: The first switching transistor Q8 has its control terminal connected to the gate of the fourth power switching device M4 and is controlled by the gate voltage of M4. The second switch Q9 has its control terminal connected to the gate of the third power switch M3 and is controlled by the gate voltage of M3. When the gate of M4 is high, Q8 is turned off, allowing high-frequency signals to be transmitted to the first resonant branch through the first amplification branch Q2 and Q3; at the same time, when the gate of M3 is low, Q9 is turned on, short-circuiting the second amplification branch Q4 and Q7, and preventing high-frequency signals from being transmitted to the second resonant branch. When the gate of M3 is high, Q9 is turned off, allowing high-frequency signals to be transmitted to the second resonant branch through the second amplification branch; at the same time, when the gate of M4 is low, Q8 is turned on, short-circuiting the first amplification branch and preventing high-frequency signals from being transmitted to the first resonant branch.

4. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: The resonant drive module includes: The first resonant unit, connected to the first power switching device M1 of the high-end half-bridge, consists of a resonant inductor L2 and a resonant capacitor C9. The second resonant unit, connected to the second power switching device M2 of the high-end half-bridge, consists of a resonant inductor L3 and a resonant capacitor C12. The first rectifier unit, connected to the output terminal of the first resonant unit, consists of high-frequency diodes D1 and D7 and filter capacitors C10 and C11, and is configured to rectify the resonant voltage into a DC voltage to drive M1. The second rectifier unit, connected to the output of the second resonant unit, consists of high-frequency diodes D5 and D4 and filter capacitors C13 and C14, and is configured to rectify the resonant voltage into a DC voltage to drive M2.

5. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: It also includes a gate discharge unit, comprising transistors Q10 and Q11 connected between the gate and source of the high-side power switching device, configured to short-circuit the gate of the high-side power switching device to the source when the corresponding resonant signal is cut off, thereby ensuring its turn-off.

6. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: The power switching device is a MOSFET, SiCMOSFET, or GaN device.

7. The control and rectification circuit of a full-bridge active bridge according to claim 1, characterized in that: The high-frequency oscillation module generates a high-frequency oscillation signal with a frequency of 385kHz.

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